Thiophosphonates containing an s-acylmethylmercapto alkyl esterifying moiety



United States Patent 3,277,115 THIOPHOSPHONATES CONTAINING AN S-ACYL- METHYLMERCAPTO A L K Y L ESTERIFYING MOIETY Karoly Szabo, Pleasantville, N.Y., and John G. Brady,

Campbell, Calif., assignors to Staulfer Chemical Company, New York, N.Y., a corporation of Delaware No Drawing. Filed Apr. 16, 1963, Ser. No. 273,301 17 Claims. (Cl. 260-3265) This invention pertains to organophosphorus compounds and in particular to thiophosphonates containing an S-alkyl ester grouping having aflixed thereto an acyl methyl mercapto moiety. The invention also pertainsto' a method of preparing the compounds and to their use as the active component in the manufacture of pesticidal compositions.

Compounds of the present invention can be depicted by the following general formula:

wherein R is selected from the class consisting of lower alkyl radicals and chlorinated lower alkyl radicals, R represents a lower alkyl radical, X is a chalcogen selected from the class consisting of oxygen and sulfur, Q is a member selected from the group designated by the formulae:

and -0 R4 in which R represents hydrogen, lower alkyl radicals, chlorinated lower alkyl radicals, R can be hydrogen, a lower alkyl radical, a phenyl radical and its halogenated derivatives, it being understood that when one of said R and R is a phenyl radical, the other is a non-phenyl substituent, or when taken together R and R constitotes a heterocyclic ring system as typified by the pyrrolidine series, the piperidine series, the morpholine series, and the like; R signifies a lower aliphatic radical, e.g. methyl, ethyl, n-propyl, tert.-butyl, sec.-butyl, allyl, meth.-allyl, propargyl, etc. or a phenyl radical, substituted or not, and n is an integer of from 1 to 2. In preparing the organophosphorus toxicants of the invention, it has been ascertained that they are realizable by a general synthetic procedure in which an organic thiophosphonate carrying a terminal chlorine substituent on the S-alkyl ester moiety is reacted with a mercaptomethyl acylated component in the presence of a base. The course of the reaction is schematically portrayed as shown in the following chemical equation:

wherein R, R X, Q and n have the significance as previously set forth. As can be seen from the chemical equation, the function of the base is to form a sodium salt of themercaptomethylacyl reactant and this is the actual entity which undergoes condensation with the organophosphorus intermediate.

-Any' basic substance can be utilized which is sufficiently strong to form the salt of the mercaptomethyl reactant and in this connection reference is made to strong organic tertiary bases, e.g. lower trialkyl amines, i.e. triethyl amine, pyridine, n-ethyl morpholine, alkali metal alkoxides, hydroxides, carbonates, e.g. sodium ethoxide, potassium ethoxide, sodium carbonate, sodium hydroxide, and the like. The reaction is conveniently carried out by refluxing the aforenamed reactants in the presence of a normally liquid, relatively inert organic solvent and for this purpose the liquid aliphatic and aromatic hydrocarbons as well as their liquid chlorinated derivatives have proven especially suitable. However, other liquid media can also .be resorted to and the general reaction is not limited to any particular solvent system.

Reference is now made to the following examples which are presented for illustrative purposes only since variations in practicing the invention without departing from the scope or spirit thereof will be apparent to those skilled inthe artto which the said invention pertains.

Example 1.-O-ethyl-S-[N-methyl-( carbarnoyl-methylthiomethyl) -ethylphosphonodithioate C1H5O 10.9 g. (0.05 M) of S-chloromethyl-O-ethyl ethylphosphonodithioate and an equivalent quantity of 2-mercapto- N-methylacetatnide were added to ml. of absolute alcohol which hadpreviously been reacted with 1.13 g. (0.05 M) of sodium. The mixture was refluxed for 4 hours after which interval the precipitated salt was filtered off and the filtrate washed with,6% sodium bi carbonate followed by a water wash. The organic fraction was dried over anhydrous magnesium sulfate and distilled in vacuo toremove the solvent and volatile components. There was obtained 11 g. of a residual, slightly viscous, pale yellow oil having an N of 1.5600. The

chemical and instrumental analysis of the product was in consonance with the above depicted structure.

Using the procedure as set forth in the first example, the following additional compounds were prepared. In general, the results and yields paralleled those obtained in Example :1.

It is to be understood that the term thiophosphonic aci andthiophosphonate as used herein is a generic expression and includes both thiophosphonic and dithiophosphonic acids and their esters.

As those in the art are well aware, various techniques are available for incorporating the active component or toxicant in suitable pesticidal: compositions. Thus, pesticidal compositions can be-convenientlyprepared in the form of liquids or solids, the latter preferably as homogeneous free-flowing dusts commonly formulated by ad mixing the active component with finely divided solids or carriers as exemplified by talc, natural clays, diatomaceous earth, various flours such as 'walnut shell, wheat, soya bean, cottonseed and so forth.

Example No. Description 13. N-methyl-4(Oethyl-chloromethylphosphonodithioyl) -3'thio- Yellow oil;

butyramlde: Np =1.5650.

ClCHz i (H) P-S-CHrS-CHz-eCNHCHs C2H O 14. Phenyl-(O-ethyl-methylphosphonothioyl)-3-thiobutyrate: v.

CH: O O II II /PSCH,SCH:CO 021150 15. O-ethyl-S-[carbomethoxymethylthiomethyll-ethylphosphono- Straw yellow oil;

tbioate: Nn =1.5l07.

C9H5 O II II P-S-CHz-S-CIh-C O CH:

CzH

16. Oethyl-(N-isopropylcarbamoylmethylthlomethyl) -ethyl- Yellow oil; N15:

phosphonothioate: 1.5250.

\ H II PSC.HzSCHzC-NHCH I A Call; CH: 1

Liquid compositions are also useful and normally comprise a dispersion of the toxicant in a liquid media, although it may be convenient to dissolve the toxicant directly in a solventsuchaskemsenegffiel oil,'xylene,alkylated naphthalenes or the like and use such organic solutions directly. However, the more common procedure is to employ dispersions of thetoxicant in an aqueous media and such compositions may be produced by forming a concentrated solution of-thetoxicant in asuitable organic solvent followed by dispersion in water, usually with the aid of surface active agents. 'Tlielatter, which may be the anionic, cationic ornonionic types, are exemplified by sodium stearate, potassium oleate and other alkaline metal soaps and detergents such as'sodium lauryl sulfate, sodiumnaphthalene sulfonate, sodium"alkyl naphthalene sulfonate, methyl cellulose, fatty-alcohol ethers, polyglycol fatty acid estersand otherpolyoxyethylene surface active agents. The proportion of these agents commonly comprises l15% by weight of the pesticidal compositions although thezproportion' isnot critical andmay be varied to suit any particular situation.

Other adjuncts may be resorted to in compounding biocidal formulations based on 'theheiein described organophosphorus esters and, in this connection, reference is'made'to adhesives, spreaders,-activators, fertilizers and the like. A

The preparation oftpesticidal compositions incorporating theorganophosphorus esters'ofthis invention and the results of testing such compositions are spelledout in the following test procedures:

Acaricidal evalu'ati0n"test.The fwd-spotted inite, Tetranychus telarius (Linn.) is employed in-tests for acaricides. Young Pinto bean plants are infested with several hundred mites. Dispersions of test compounds are prepared by dissolving 0.1 gram of the toxic' material in ten milliliters acetone. water containing 0.015% vatsoltsodium salt of isopropylnaphthalene sulfonate) and 0.005% Methocel (methylated cellulose) as emulsifiersflhe amount of water being sufficient 'to give concentrations of active ingredient ranging from 0.25% to 0.005%. The test suspensions are then sprayed on the infested Pintobeamplants. After seven and fourteen days, the plants are examined both for post-embryonic forms of .themite as well as eggs. The percentage of kill is determined by comparison with control plants which have not been sprayed and the LD-.

This solution is then diluted with 50 value calculated using well-known procedures. LD-SO values are reported under the columns 2 SM and 2 SM eggs on the table below. 7

Systemic toxicity evaluation against two-spotted mites.Pinto bean plants in the primary leaf stage. are placed in 250ml. capacity Erlenmeyer flasks, one plant per flask. A portion of the test compound is-dissolved in 10 ml. of acetone. This solutionis diluted with disstilled water in an amount suflicient to give concentrations of active ingredient ranging -from parts per million (p.p.m.) to l partper million. The final volume of test dispersion per flask is 200 ml. The treated plants are infested with several hundred two-spotted :mites, Tetranychustelarius (Linn.). After seven and fourteen days, the plants are examined for1post-embryonic forms of the mites as well as eggs. Thepercentage of kill is determined by comparison with control plants which have beenplaced in distilled water only. The results 'are.re-' ported in the table nnder'2 SM Systemic.

Insecticidal evaluation -tests.-Four insect species at subjected to evaluation tests for insecticides: I

( 1) American cockroach (AR) 'Periplaneta a-mericana (Linn.) (2) Milkweed bug (MWB) Oncopeltus fasciatus (Dallas) (3) Confused flour beetle (CFB) Tribolium confusum (Duval) (4) House fly (HF) Musca domestic-a (Linn.)

The procedure for insects is similar to the miticidal testing procedure. Test insects are caged in cardboard mailing tubes 3% in diameter and 2%" tall. The cages are supplied with cellophane bottoms and screened tops. Ten to twenty-five insects are used per cage. Food and water are supplied in each cage. The confused flour beetles are confined in petri dishes without food. The caged insects are sprayed with the active compound at various concentrations. After twenty-four and seventytwo hours, counts are made to determine living and dead insects.

House fly evaluation tests differ in this respect: the toxicant is dissolved in a volatile solvent, preferably acetone, the active compound is pipetted into a-petri dish bottom, allowed to air dry and placed in a cardboard mailing tube. Twenty-five female flies are caged in the tube. The flies are continuously exposed to the known 3,277,115 7 8 residue of the active compound in the cage. After twenty- 6. An organophosphorus compound of the formula: four and forty-eight hours, counts are made to determine C2115 i (If living and dead insects. The LD-SO values are calculated P S CH2OH2 .S CHT O0O2H5 using well known procedures. OZHSO Data fi-om testmg the compounds of mvemlol} are 7. An organophosphorus compound of the formula: reported in the table below; the concentration of toxicant 02m S is indicated as parts per million or as percent; ,ug. refers H to micrograms and represents the quantity of toxicant re- P S CH S CH CNHCH3 ceived by a single pest organism. CHSO TABLE 2 sM Example HF, g. AR, MWB, SMC,

percent percent percent PE, E, Syst., percent percent p.p.m.

We claim: 8. An organophosphorus compound of the formula: 1. An organophosphorus compound of the formula: C2115 S H H CH3 I"scH:s0Hi NHoHa R- P-S- (0H1) nSCH2 C Q CHO R1 CH3 wherein R is selected from the class consisting of lower 9. An organophosphorus compound of the formula: al-kyl and chloro lower alkyl, R represents lower alkyl, 7 C2115 S O X is a chalcogen selected from the class consisting of N H n oxygen and sulfur, Q is a member selected from the group P S C OH? SCH2 (JNHCH3 designated by the formulae C2H5O 10. An organophosphorus compound of the formula:

-N and -0B4 40 01H. s 0 CH3 ll Ra PS-CH2CHISCHg-CN wherein R is selected from the class consisting of hydro- (3,1150 CH3 gen and lower al-kyl, R is selected from the class con- 11 An or ano hows com ound of the, formula. sisting of hydrogen, lower alkyl, phenyl, chlorophenyl, g p Sp p it being understood that when one of said R and R is fi H phenyl, the other is a non-phenyl substituent, and taken PSCHz-S-CHz-GNHCH together R and R can complete a heterocyclic ring se- CHaO CH3 lected from the group consisting of pyrrolidine, piperidine and morpholine, R is selected from the class con- An 9 compound of the formula sisting of lower aliphatic and phenyl, and n represents 0111K IsI (I? /o11,-0H, an integer from :1 to 2. P-S-CHz-S-CHz-CN 2. An organophosphorus compound of the formula: CHSO OH? H,

S 13. An organophosphorus compound of the formula:

P-S-CHrS-CHrCNHCH: 02H5 S o I 011150 i -s-oHr-s-cm NH- 3. An organophosphorus compound of the formula: CHBO/ C H s 2 14. An organophosphorus compound of the formula: PSGH;SCH COCzHs 01011 S i CzH5O II P-S-CHz-S-CHr-CNHCHI 4. An organophosphorus compound of the formula: CHSO C H S 2 u u 15. An organophosphorus compound of the formula:

PSCHrSCHzCOCzHs CH 0 II i ll 3 P-S-CHz-S-CHrC-O-Q 5. An organophosphorus compound of the formula: 02H

C135 3 H 16. An organophosphorus compound of the formula: OH3\ Ps-cHT-s0H;-00c2H5 (hm O o 9 10 17. An organophosphorus compound of 1-116 formula: 3,021,351 2/1962 Schegk 61; a1. 260 461.110 mm 0 3,086,974 4/1963 'Schl'or et a1. 260 461.110 \n n 3,090,719 5/1963 Pinamonti 167--22 P S CH S CH CNH CH 3,094,405 6/1963 P011 Toy et a1 71-23 CH5 3 5 3,094,550 6/1963 $011101 et a1. 260 461.110

References Cited by the Examiner OTHER REFERENCES UNITED STATES PATENTS Kabachnik Zhur. 01551161161 Khim, V01. 28, pp. 1568 2,861,023 11/1958 S'c'ot-t et a1. 167 -22 1573 (1958) et 2,881,201 4/1959 Schrader 260461 10 2,881,202 4/1959 Pianfetti et a1. 260461 CHARLES PARKER Examme" 2,943,974 7/1960 Metivier 260 461.112 JULIAN s. LEVIIT, GEORGE A. MENTIS, FRANK 2,961,458 11/1960 Schegk e: a1. 260461.110 M. SIKORA, Assistant Examiners.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,277,115 October 4, 1966 Karoly Szabo et a1.

It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent Should read as corrected below.

Column 2, lines 29 to 51, the formula should appear as shown below instead of as in the patent:

fl 0 C H 2 PS-CH S-CH -CNHCH C H 0 2 2 3 Signed and sealed this 5th day of September 1967.

(SEAL) Attest:

ERNEST W. SW'IDER Attesting Officer EDWARD J. BRENNER Commissioner of Patents 

1. AN ORGANOPHOSPHORUS COMPOUND OF THE FORMULA:
 12. AN ORGANOPHOSPHOROUS COMPOUND OF THE FORMULA: 